Steam iron



.JQYOUHOUSE Aug. W 11 956 STEAM IRON Filed Aug. 17, 1955 INVENTOR 3 0710mm Mime fin States Patent cc 2,757,464 Patented Aug. 7, 1956 STEAMIRON Joseph Youhouse, Fairfield, Conn., assignor to Casco ProductsCorporation, Bridgeport, Conn, a corpora= tion of ConnecticutApplication August 17, 195-3, Serial No. 374,787 3 Claims. (Cl. 38-77)This invention relates to steam-electric flatirons of the type havingheated sole plates and steam chambers associatcd with the sole plate.

The invention is illustrated herein in connection with a flash-boilertype of steam electric iron, that is to say, an iron wherein anadjustable metering valve causes water to drip into a heated chamber andbe flashed into steam which is discharged against the work throughoutlets in the sole plate.

My invention disclosed herein is a species of that disclosed and claimedin my copending application, Serial No. 125,791, filed November 5, 1949,now Patent No. 2,652,645.

in general, a flash-boiler type steam iron comprises a Water tankdisposed above a heated sole plate and having an adjustable meteringvalve by which water drops may be supplied to a heated flash chamber inthe sole plate, said chamber being connected through suitable channelsto steam outlets or ports in the bottom of the sole plate. Such ironsare designed for use alternately as steam irons and dry irons. Thethermostatic control of such an iron is arranged to permit temperaturesas high as 500 P. which is a desirable heat to iron linen articles.

However, if an attempt is made to use the iron as a steam iron attemperatures over approximately 350 F. it is known that the drops ofwater falling on the flash plate will ball-up, i. e. become spherical,bounce around on the plate and pass out of the chamber into the material being ironed as discrete unvaporized water particles. This is knownas sputtering and may result in spotting the article being ironed oreven cause skin burns should the iron be suddenly upended Whilesputtering.

To meet this diiiiculty, manufacturers of flash-boiler type steam ironsindicate, within the range of settings of the thermostat, a certainrestricted range for which the iron is to be used as a steam iron; sucha range, for example, might be from 235 F. to 350 F., and users areadmonished that if higher or lower sole plate temperatures are required,then the iron should be used as a dry iron and the water valve should beclosed. These irons are admittedly unsuitable for steam ironing attemperatures above 350 B, because of the excessive spitting orsputtering from the sole plate. It is well understood that tosatisfactorily press articles of certain fabrics, such as woolen orlinen articles, heat above 350 F. and moisture are required. Hence theflashboiler irons as heretofore produced had to be used as dry ironswith the moisture being supplied by dampening the fabric or by the useof a damp pressing cloth, steps which the use of a steam iron isintended to obviate.

An object of the present invention is to provide a flash-boiler typeiron which may be operated and made to steam at temperatures above thepresent indicated steaming range without sputtering or discharge ofwater droplets from the steam openings in the sole plate, therebyenabling the iron to steam press fabrics requiring high temperatureswithout the use of a damp pressing cloth, or without first dampening thefabric itself.

A further object of the invention is to provide an improved steamelectric iron as above set forth, which has relatively few parts and isof simple construction, and is economical to manufacture and reliable inits operation.

The above objects are attained by the provision of a novel and uniqueflash plate in the steam chamber of the iron, on which the water dropsfall, said plate being characterized by a rough and irregular orbroken-up top surface as effected by the presence of many, small,closely-spaced sharp projections or ridges disposed in the path of thewater drops. When the water drops strike such a rough surface, it hasbeen discovered, they are quickly dispersed, the formation of balls orspheroids being prevented and the water becoming completely converted orflashed into steam. By my novel flash plate construction as set forthherein there is completely eliminated the discharge of water dropletsfrom the steam ports of the sole plate for even the higher temperaturesettings of the thermostat. i have found that sole plate temperatures ashigh as 475 F. to 500 R, which is the desirable heat for ironing linen,may be employed without causing the objectionable sputtering ordischarge of water from the sole plate, which is encountered inflash-boiler type irons heretofore produced.

In one embodiment of the invention shown and described herein, the fiashplate is constituted by the floor of the steam chamber, which latter isformed by a depression or cavity in the upper surface of the sole plate.The floor of the cavity which is contacted by the water drops from thetank, is provided with a multiplicity of relatively sharp,closely-spaced ridges and/or pyramidal nibs or points closely spacedfrom each other, the latter being formed for example by the intersectionof grooves with other grooves extending transversely thereof.

In another embodiment of the invention, there is provided a separatepiece of sheet metal, having the ridges, nibs, projections and the likeon its upper surface and this is mounted on the sole plate inside thesteam chamber, to constitute the floor thereof on which the water dropsfall.

By the provision of the improved flash plate of this invention withroughened surface as above set forth, the steaming time, i. e. the timewhich is required to convert water into steam, is greatly reduced, andthis is an advantageous feature of the invention.

Other features and advantages will hereinafter appear.

In the accompanying drawings:

Figure 1 is a side view partly in elevation and partly in verticalsection, of a steam electric iron embodying the invention.

Fig. 2 is a plan view of the electrically heated sole plate of the ironof Fig. 1, shown with the cover of the flash chamber secured in place.

Fig. 3 is an enlarged fragmentary plan view of a section of the floor ofthe flash chamber, showing the roughened surface thereof by which thedrops of water are quickly dispersed and flashed into steam.

Fig. 4 is a fragmentary section taken on line i-4 of Fig. 3.

Fig. 5 is a fragmentary vertical section taken on line 5-5 of Fig. 3.

Fig. 6 illustrates a modification of the invention, being a fragmentaryplan view of a section of the bottom wall or floor of the flash boiler,provided with a separate member having a roughened surface.

Fig. 7 is a fragmentary section taken on line 7-7 of Fig. 6.

Referring to Figs. 1 and 2 the steam electric iron shown thereincomprises an electrically heated sole plate ill having a sheathedheating element 11 cast into it, the sole plate mounting a casing 12 towhich a handle structure 13 is secured.

Within the casing 12 there is carried a water tank 14 connected to afilling pasage 15 which is disposed in a bore 16 of the front post 17 ofthe handle structure. The passage 15 has secured to its forward wall athimble or ferrule 18 disposed in a transverse filling opening 18a inthe front wall of the hollow post 17 of the handle structure.

Adjustment of the temperature of the heating elen ent 11 is effected bya manually-operable thermostat control knob 19 which effects theregulation through a shaft 20 and cam plate 21, the latter actuating anarm 22 which may be connected to any suitable, heat-responsive controlswitch as is well understood in the art. Such control. switch forms nopart of the present invention and accordingly a showing thereof is notprovided herein.

The electrically-heated sole plate 10 is provided with a cavity 23 belowthe forward portion of the water tank 14, said cavity constituting asteam or flash chamber by which drops of water supplied from the tankare flashed into steam and the steam ejected from the sole plate. Thesole plate 10 has steam discharge openings 24 communicating with a steamdistribution chamber 25, the latter being separated from the flashchamber 23 by a wall or partition 26 extending generally in a V-shape,Fig. 2. In this figure the partition 26 is shown as having a pair ofopenings 27 providing for communication between the flash chamber 23 andthe steam distribution chamber 25. The top walls of the chambers 23 andare constituted of a cover plate 28 which has a portion 29 engaging thepartition or wall 26 to prevent passage of steam between the chambersexcept through the openings 27 intended for such passage.

Referring to Fig. l the cover plate 28 has an upstanding portion 30 onwhich a metering valve structure 31 is mounted, said structure having avalve seat 32 and a needle valve 33 cooperable with the seat and mountedfor movement in the hollow front post 17 of the handle structure 13. Thestem of the needle valve 33 passes through an apertured top wall 34 ofthe filling passage 15 of the tank 14 and at its upper end is providedwith an operating knob 35' shown in valve-opening position and which maybe depressed to, and latched in, a valve closing position as indicatedby the dotted outline 36.

When the iron is to be used as a dry iron the knob 35 is placed in itsdepressed position closing the valve, and when the iron is to be usedfor steam ironing the knob 35 is released to its raised position, shownin Fig. 1, wherein the needle valve 33 is free of the valve seat 32. Forsuch condition, Water from the tank 14 will flow drop by drop into theflash chamber 23 to be converted into steam and thereafter dischargedfrom the ports 24 of the sole plate 10.

Heretofore flash-boiler type irons have been limited, as to theirsteaming range, and a restricted zone has been indicated in conjunctionwith the manually-operable thermostat knob 19, wherein the iron may beused for steam ironing. If the thermostat knob 19 is set either belowsuch range or above such range the iron will sputter and discharge waterthrough the said ports 24 of the sole plate, for the reason that thewater will not be converted into steam. At the lower temperature thereis insuflicient heat in the flash chamber 23 of the sole plate toconvert the water into steam, and at the higher temperatures the waterwhich is dropped into the flash chamber balls up and bounces around, andis discharged through the communicating openings 27 and through the soleplate ports 24. Such discharge of water is undesirable because, aspreviously pointed out, it results in spotting of the fabrics beingironed and in a generally unsatisfactory pressing operation, as well asbeing a potential safety hazard.

According to the present invention I provide a novel and advantageousflash plate or surface in the steam chamber 23, disposed in the path ofthe water dripping from the metering valve 31, which is characterized bya large number of sharp, pointed projections by which the drops of waterare prevented from balling up and being discharged from the steamopenings of the sole plate but instead are quickly dispersed andcompletely converted into steam even though the sole plate and steamchamber temperatures are higher than the present indicated steamingrange. Whereas heretofore the maximum indicated steaming setting of thethermostat knob 19 has corresponded to a sole plate temperature in theneighborhood of 350 F., by the provision of my improved steam chambersurface, sole plate temperatures as high as 475 F. to 500 F. may beemployed without adversely affecting the complete conversion of thedrops of water from the tank 1 into steam.

In the embodiment of the invention illustrated herein, see Fig. 3, thisis accomplished by providing the floor surface of the flash chamber 23with sharp, parallel V-shaped ribs 37, Figs. 3 and 4, said ribs formingbetween them V-shaped grooves 13%. The ribs 37 are preferably on theorder of high and are spaced apart although these dimensions may bedeparted from within limits without materially affecting the quickconversion of the water droplets into steam.

I also provide a plurality of transverse or cross ribs 39, and these mayconveniently be formed as concentric, intersecting the ribs 37 andresulting in a large number of minute, pyramidal projections 40 risingfrom the floor of the flash chamber 23. The concentric ribs 39 arepreferably also high and approximately apart, resulting in the pyramidalprojections 50 being of corresponding height and correspondingly closelyspaced.

When the floor surface of the flash chamber is so roughened or providedwith projections as above set forth, it results in water drops receivedfrom the metering valve 31 being quickly dispersed and flashed intosteam at elevated sole plate temperatures, and prevents such drops fromballing up and bouncing around in the flash chamber and being dischargedfrom the steam ports 24 to soil a fabric or otherwise impair the steamironing operation. Preferably the roughening of the floor surface issuch that a large number of closely-spaced, sharp or pointed projectionsis presented where the drops of water fall, and I have found thatprojections as thus characterized are most efficient in quickly andcompletely flashing the water into steam.

Moreover, the provision of the rough flash surface as above set forthgreatly lessens the time required to produce steam. As an example, for asole plate temperature of 500 F. the steaming time is reduced fromapproximately one minute to approximately 15 seconds by converting thesmooth flash surface to a rough surface in accordance with theinvention.

In Figs. 6 and 7 the sole plate 10:: is provided with a separate pieceor member 41 of metal more corrosionresistant and harder than the soleplate, having a roughened upper surface 42 produced by the formation ofthe large number of closely-spaced, sharp, pointed projections describedabove, the projections remaining sharp and effective to flash water intosteam throughout the life of the iron. The separate piece 41 may befastened to the sole plate 10a by any suitable means such as the screw43 shown in Figs. 6 and 7. This form of the invention may beadvantageously employed where it is inconvenient to mill or otherwiseprovide the roughened surface on the sole plate itself. By the provisionof the separate piece 41, the projections may be formed in the mostconvenient and desirable manner without regard to limitations whichwould otherwise be imposed by the shape, size or material of the soleplate.

While I have shown the floor of the flash chamber 23 immediately belowthe metering valve 31 as being provided with the roughened surface forquickly flashing water droplets into steam it is understood that anyheated surfaces within the flash chamber or steam distribution chamberof the iron may be similarly equipped, Where there is a likelihood ofglobules of water coming in contact with said Walls and not beingquickly converted into steam.

Variations and modifications may be made within the scope of the claimsand portions of the improvements may be used Without others.

I claim:

1. In a steam iron having a Water tank, a sole plate under the tank, anelectric heating element arranged to heat the sole plate and a flashchamber formed in the sole plate, said tank being spaced out of directheatreceiving relation over the sole plate and over the flash chamber, aWater passage having a metering valve unit therein, for dischargingWater from the tank in drops to the flash chamber, and steam escapepassages through the sole plate communicating With the flash chamber andspaced from the outlet of said Water passage; the improvement whichcomprises the provision of a rough surface forming the floor of theflash chamber under the outlet of the Water passage for enabling theWater drops to be flashed into steam, said rough surface com prising aplurality of peaks extending upwardly from the floor of the flashchamber under the outlet of the Water passage, the distance betweenpeaks being not substantially greater than the height of the peaks, saidpeaks breaking up Water drops entering the flash chamber and preventingthe same from balling up and passing as discrete water particles throughthe said steam escape openings of the sole plate.

2. The invention as defined in claim 1 in Which there is a separatemember carried by the sole plate in the flash chamber, said memberhaving the said rough surface.

3. The invention as defined in claim 1 in Which the peaks are formed byparallel ribs in the order of high and spaced in the order of A apart.

References Cited in the file of this patent UNITED STATES PATENTS1,213,602 Durand Jan. 23, 1917 2,317,706 Woodman Apr. 27, 1943 2,350,452Envall June 6, 1944 2,371,569 Wolcott et a1. Mar. 13, 1945 2,652,645Youhouse Sept. 22, 1953

